Luminaire



Sept. 22, 1925.

1,554,563 w. A. DOREY LUMINAIRE Filed Oct. 21. 1924 2 Sheets-Sheet 1 INVENTOR Z9 Pl z'ZZz'n-m [Zflorey -a ATTORNEY Sept. 22, 1925.

W. A. DOREY LUMINAIRE Filed Oct. 21 1924 2 Sheets-Sheet 2 IN l/E N TOR WZZz anz [L Darcy A TTOR/VE Y Patented Sept. 22,1925.

1,554,563- UNITED STATES PATENT, OFFICE.

or NEW JERSEY.

' LUMINAIRE.

Application flledooctober 21, 1924: Serial No. 744,881.

To-all whom it may concern:

Be it known that I, WILLIAM A. Down, a citizen of the United States of America, and a resident of Newark, in the county of Licking andState of Ohio, have invented certain new and .useful Improvements in a Luminaire, of which the following is .a specification.

The object of this invention is the manufacture of a luminaire of the refractorj type, preferably employed 'in street lighting which can be effectively used at or near the curb, so as to light up the road and street effectively and to keep the neighboring houses either in comparative darkness or to transmit a portion of the light to them for ornamental or utilitarian purposes.

Fig. 1 is a vertical cross section of a luminaire embodying my invention.

' Figs. 2 and 3 are diagrams of photometric curves showing the distribution obtained. Fig. 4 is a vertical cross section of a modified form of luminaire embodying my invention.

Fig. 5 is an end elevation of the inner glass showing a prism modification which may be employed. i

In Fig. 1, 1 is a lamp having light source 2 considered as a point. The upper portion of thelamp is enclosed in a compound refracting and reflecting glass consistingof an inner cover 3 and outer cover '8. The inner cover has preferably a smooth inner surface 7, while its outer surface is provided onone half with horizontal refracting prisms 4. The lower part of the other half of the outer surface is provided with radial double reflecting prisms 5, while the upper part 'of this half is provided with radial double reflecting prisms 6 of reater width and depth than prisms 5 and projected beyond the contour of prism 5. The lower part .of this inner cover is made of such a contour that the light striking the. reflecting portion will be reflected across the axis of the lamp at wide angles. The upper part is of such a'contour that the light striking the reflector side will be reflected across the axis and beneath the opposite edge of the luminaire.

Outer cover 8 has preferably an entirely smooth outer surface face of one half of 8 isprovided with refracting prisms 9 and the interior of the opposite half is provided with horizontal scattering flutes 10.. The covers over each other so that 11: The interior sur f are placed face each other. That half of the combination which is provided with refracting prisms has its outer surface and both sets of refracting prisms so disposed with reference to each other that they will cooperate with the inner surface which is already determined by the reflecting requirements, in such a way as to retract and transmit the light intercepted by it in a substantially parallel beam slightly below the horizontal. surfaces may operate throughout the length of the refractor to depress the light'and at, the sametime'to permit successful mann In order that the refracting WILLIAM A'. DOREY, or NEWARK, 01110, AssIeNoR T0 HOLOPHANE GLASS COMPANY, I OFNEW YORK, N. Y., a CORPORATION the refracting prisms facture of the refract ing prisms on the outer piece, the lowerpart of the outer piece is cupped in at 12. 1

The course of typical light rays is shown to indicate the operation of the various parts of the refractor. The portion of the units having. refracting prisms are placed together in the manner shown on the side toward the street, while the portions containing radial reflecting prisms and scatflutes are placed together toward the tering houses.

Ray 13 proceedingfrom the light source isrefracted and transmitted as shown in the direction 14. The action of this ray is typical of the action of all rays coming direct from the lamp and intercepted by refracting prisms 4 and 9. Ray 15 will in part be reflected in the direction 16 parallel.

to emitted ray 14 and will in part be transmitted in direction 17. the operation of all light ra s direct from the source intercepted by reflecting prisms 5. Ray 20 direct from the source is in part reflected in direction 21, passing beneath the oppositeedge of the'luminaire at an angle somewhat lower than emitted rays 14 and 16. Ray 20 direct from the source will in part be transmitted in direction 18? This is typical ofthe action of all li ht rays direct from the source intercepted bythe reflecting prisms 6. The transmitted portion This is typical of of rav 15 strikes the upperedge of one of the flutes 10. Rays emitted by the source in directions immediately below ray 15 will in part be transmitted to lower portion of this same flute and scattered in' directions19,

19. In the same way the transmitted por-' tion of ray 20 strikesthe lower edge of one of the flutes and neighboring rays emitted a from, the source. at an angle above that of ray 20 will in part be. transmitted to upscattered .The lateral distribution in any cone will tend to besubstantially equal through ISOdegrees on the house side but the intensities throu h the half cone of the house side will di er -from the intensities through the half cone on the street side. The vertical distribution on the street side will be similar to typical street lighting distribution intensified by the action of the reflector part but the vertical distribution on the house side will be much lower in intensity at wider angles below the horizontal, some ofthe upward light being refracted back to the other side and thebalance transmitted and scattered in vertical planes.

In- Fig. 2 a typical vertical distribution curve 23 tor a symmetrical refractor is shown made up throughout in the construction shown at4 and 9, Fig. 1. Vertical distribution 24 is typical of the combined construction shown in Fig.- 1, lobe 25 being that emitted toward thestree't and lobe 26 being v that emitted toward the buildings.

In Fig. 3 a typicallateral distribution curve 27 in .a cone 75 degrees from nadir I :for a symmetrical refractor is shown. Vertical distribution 28'is typical of the combined construction shown in Fig. 1, lobe 29 being that' emitted toward. thestreet and lobe 30 being that'emitted toward the build- 111% en it is desired to increase the illumination on the. buildings the modification shown in Fig. 4.- is provided, in which the retracting construction 4-and19 and-=the scattering construction 10 are the same as in Fig. 1; also the lower reflecting construction 5 is similar to that in Fig. 1. The upper part of the inner reflecting halt is provided pn its outer surface with horizontal scattering flutes 31. At 32 are shown bunwill be to decrease slightly the lobe 25 dles of light rays roceeding from the source and intercepte by flutes 31. These rays will be scattered as shown by the flutes 31 and will be given still wider divergence byv theflutes 10 on the outer piece so that they will be'emitted in directions 33, 33, 33 etc I I q The efiectof thismodification on the distribution of 'light as illustrated in 5 thepoint of maximum intensity and to increase lobe 26 above the horizontal.

The. distribution shown in Fig. 3 will remain substantially the same.

This device may be used within large slightly diffusing enclosing globes and in such cases if the reflecting and retracting parts are divided by a definite division line, the reflector portion will cast a well defined shadow on the enclosing globe when the light source is in operation. Fig. 5 shows an end elevation of the inner glass modified so that the edges of this shadow will be softened. "Thereflecting prisms 5 and 6 immediately adjacent to the refracting prisms 4, are partially cut away at their bases by the refracting sections 34, which are of the same vertical section as refracting prisms 4 andof gradually reducing area as shown. In addition to this, in order to break upth'e shadow at the lower edge of the (glass, refracting sections 35 are provide cutting the bases-of the lower ends of all of the reflecting prisms 5 and each succeeding upward tier of theserefracting sectlons is of reduced area. The action of these refracting sections isto allow gradually decreasing portions of the light striking the edges of the reflector-portlon to be transmitted and this in effect produces a gradual shading of the edges. of the shadow cast upon the enclosing globe.

I claim:

-1.' A luminaire comprising a light source and a double glass cover enclosing the same, theinner envelope of the cover having on one portion a series of radial double reflecting prisms adapted to reflect the major portion of incident light'rays below the lower edge of the opposite side of the unit and opposite thereto a series of horizontalrefractmg prisms adapted to deflect light downward. the outer envelope of the cover being provided on the portion superimposed above .the radial prismatic portion with flutes adapted to scatter the portion of light transmitted by the radial prisms and on the portion superimposed above the. refracting prisms of the inner cover with a series of refracting prisms adapted to bend the light downwa dly- 1 i 2. A luminaire comprising a light source and a double glass cover enclosing the same,

the inner envelope of the cover having on. one portion of its exterior a'series of radial double reflectingprisms adapted to reflect the major portion of incident light raysbelow the lower edge of the opposite side of the unit and on its exterior opposite thereto a series of horizontal refracting prisms 'adapted to deflect light downward, the outer envelope of the-cover being provided on the portion superim sed above the radial prismatic portion with flutes adapted to scatter -the portion of light transmitted by the radial prisms and on the portion superimposed above the refracting prisms ofthe inner cover with a series of refracting prisms adapted to bend the lightdownwardly.

macros 3. A luminaire comprising a light source and a double glass cover enclosingthe same, the inner envelope of the cover having on one portion of its exterior a series of radial double reflecting prisms adapted to reflect the major portion of incident light rays below the lower edge of the opposite side of the unit and on its exterior opposite thereto a series of horizontal retracting prisms adapted to deflect light downward, the outer envelope of the cover being-provided on its interior on the portion superimposed above the radial prismatic portion with flutes adapted to scatter the portion of light transn'iitted by the radial prisms and on its in.. terior on the portion superimposed above the refracting prisms of the inner cover with a series of refracting prisms adapted to bend the light downwardl 4:. A luminaire comprising a light source,

and a double glass cover enclosing the same,

the inner envelope of the cover having on one portion near the neck a series of horizontal scattering corrugations and adjacent below a series of radial double reflecting prisms adapted to reflect the major portion of incident light rays below the lower edge of the opposite side of the unit and opposite thereto a series of horizontal refracting prisms adapted to deflect light downward, the outer envelope of the cover being provided on the portion superimposed above the radial prismatic portion with flutes adapted to scatter the portion of light transmitted by the radial prisms and on the portion superimposed above the retracting prisms of the inner cover with a series of refracting prisms adapted to bend the light downwardly.

5. A luminaire comprisinga light source and a double glass cover enclosing the same, the inner envelope of the cover having on one portion of its exterior near the neck a series of horizontal scatterin corrugations and adjacent below a series 0 radial double reflecting prisms adapted to reflect the major portion of incident light rays below the lower edgeof the opposite side of the unit and opposite thereto on its exterior a series of horizontal retracting prisms adapted to deflect light downward, the outer envelope of the cover being provided on its exterior on the portion superlmposed above the ra dial prismatic portion with flutes adapted to scatter the portion of light transmitted bythe radial prisms and on its interior on the portion superimposed above the refracting prisms of the inner cover with a series of refracting prisms adapted to bend the light downwardly.

Signed at Newark, in the county of Licking and State of Ohio, this 18th day of October, 1924. i 7

WILLIAM A. DOR'EY. 

